Recently, display devices such as liquid crystal display devices and organic electroluminescent display devices have been put into practical use. In the manufacturing process of the display device, various operation inspections such as an illumination inspection are performed. The inspection device applied to the inspections needs to comprise probes to supply inspection signals together to pads formed in the display device. For example, technology of reducing the number of probes required for the inspections by integrally forming circuits for array inspection and circuits for cell inspection has been disclosed.
In contrast, if the number of channels of a signal source of the inspection device exceeds the total number of pads of the display device or the total number of probes of the inspection device or if the total number of pads or the pitch between the pads (or pad layout) is varied in accordance with product specifications, the probes need to be designed again and manufactured, which causes increase in the manufacturing costs and reduction in the inspection efficiency.